Pump for refrigerating devices



June 19, 1934. H. HENDRIKS ET AL PUMP FOR REFRIGERATING DEVICES.

Filed Dec. 29, 1932 2 Sheets-Sheet l June 19, 1934. H. HENDRIKS EIAL 1,963,993

PUMP FOR REFRIGERATING DEVICES Filed Dec. 29, 1932 b m v 2 Sheets-Sheet 2 l'nwsqfors.

Patented June 26 1934 UNITED STATES PATENT OFFICE PUMP FOR REFRIGERATING DEVICES Ontario, Canada Application December 29, 1932, Serial No. 649,270

9 Claims.

The principal objects of this invention are to provide a small compact unit which may be .operated-at extremely low cost and will function silently and will cost very little to operate.

' The principal feature of the invention consists in'the novel construction and arrangement of a unit for compressing the refrigerant whereby the continuous flow of a non-compressible fluid intermittently operates a diaphragm operating in an enclosed chamber to compress the fluid refriger ant, the intermittent operation being efiected by a pressure-operated release valve.

A further and important feature consists in the novel assembly of the device whereby a gear pump directly connected with an electric motor circulates the non-compressible fluid through the diaphragm chamber.

In the accompanying drawings, Figure 1 is a plan view of the refrigerating unit.

Figure 2 is a side elevational view.

Figure 3is an enlarged sectional detail of the diaphragm pumping device and the oil pump for operating same.

In the invention herein shown the electric mo- 25 tor 1 which is of the split phase type is mounted on the base 2 and the bell end 3 of the motor casing has mounted on one end thereof the gear pump casing 4. The motor shaft has mounted on one end thereof the pump gear 5 which meshes with a gear 6 to force a stream of non-compressible fluid such as oil through the compressor device. The compressor is here shown in the form of a cylindrical casing '7 secured to the base 2. This casing is formed with a convergent top 8 '5, which-merges into a flange 9.

The upper surface of the flange portion of the casing is dished downwardly forming a semiovalshaped'recess 10. 1

A cap 11 encloses the flange 9 and is formed with a semioval recess 12 on the opposite'curvature tothat of the recess 10.

Between the cap and the flanged casing is secured a flexible diaphram 13 which may be formed of leather, rubber or any other strong flexible material; This diaphragm is rigidly clamped between the meeting flanges of the casing and cap and the central portion is adapted to flex within the ovoid chamber formed by the recesses and A central-circular recess '14 is arranged in the bottom of the recess 10 and is covered by a heavy perforated screen 15. The recess 14 is connected with thedischarge pipe 16 on the gear pump and theoil under pressure is forced thereinto by said 5' pump and exerts a pressure through the perforated screen 15 against the bottom of the diaphragm.

The cap 11 is provided with a port 17 through which the refrigerant fluid is forced by thejupward movement of the diaphragm against the bottom of which the fluid pressure is exerted by the gear pump. The port 17 is controlled by the exhaust valve 18 to prevent a return of back pressure.

A port 19 controlled by an intake valve 20 allows the return of the refrigerant fluid to the diaphragm chamber. This'port is larger than the discharge port and is preferably covered with a perforated screen 21 to prevent distortion of the diaphragm when it is pressed upwardly by the fluid pressure.

A small circular port 22 opens from the bottom of the recess '14 below the diaphragm chamber and communicates with a larger circular chamber 23.

A flanged circular member 24 is secured in a flanged opening 25 in the bottom of the casing? and this member is provided with a central circular boss 26 which has a cylindrical chamber 27 therein. Holes 28 extend through the side walls of the boss 26 entering the chamber 27 near the bottom to permit the inflow of fluid from the body of the main casing '7.

' A piston 29 operating in the chamber 2'7 is provided with a cylindrical end 30 which is flanged to engage the portion of the central member 31 of the main casing '7 surrounding the circular chamber 23 and forms a valve to close said chamber;

Within the cylindrical end 30 of the piston 29 is mounted a piston valve 32, the end of which engages the underside of the casing through which the port 22 extends and forms a valve toclose said port. The movement of the piston valve 32 is limited by a pair of pins 33 which are secured in the side wall thereof and extend into slots 34 in the side walls of the cylinder end.

A coil compression spring 35 is arranged'inside of the valve 32 and holds the valve 32 against the port 22 to keep it closed against a predetermined pressure.

A compression spring 36 is arranged in the cylindrical chamber 27 and engages the bottom of the piston valve 29 and presses it upwardly against its seat, closing the chamber 23 with a pressure greater than the pressure exerted by. the spring 35. I i V r The relative values of these'springs is such that the spring 35 will release the valve 29, sliding it within the main valve allowing the oil pressure back of the diaphragm to flow into the chamber 23 which then acts against the larger diameter and ultimately overcomes the pressure of the spring 36 and allows the instantaneous release of the pressure behind the diaphragm.

The gear pump forcing oil under pressure continues to operate, but the oil flows freely while the Valves described are open.

The return pressure of the refrigerant presses the diaphragm down to its lowermost position and upon the release of the back pressure the spring 36 immediately returns the piston valves to their position to close. The gear pump then creates a pressure in the chamber below the diaphragm again forcing it upwardly to discharge the refrigerant from the diaphragm chamber. This operation continues indefinitely, the valve mechanism described operating automatically to release the pressure of oil and allow the return of the diaphragm to its normal position without any mechanical trip of any kind.

Immediately the valves open, the fluid pressure is equalized through the holes 28 and the spring 36 returns the piston valve 29 to its closed position.

The action is extremely simple and also very fast.

Split phase motors are very cheap and they can be used to operate a mechanism such as described as there will be no torque in starting as thereis no pressure to start against.

The gear pump is directly connected with the motor shaft and is completely sealed. No crank shaft seal is necessary.

The compressed refrigerant is carried through the pipe 37 to the condenser 38 and from thence it is conducted by the pipe 39 through a strainer 40 and choke tube 41 to the evaporator 42 from whence it returns to the compressor through the pipe, 43.

The simplicity of construction and economy of operation of this unit will be readily apparent and a refrigerating unit of extremely desirable form is produced.

- It will be appreciated that with the diaphragm construction the back pressure of the refrigerant is definitely limited so that there is no back. pressure exerted against the operation of the mechanical parts.

it will be further appreciated that the back pressure of the refrigerant may be used to operate the controlling valves.

A decided advantage is also obtained through the complete separation of the lubricant from the fluid refrigerant.

What we claim as our invention is:-

1. In a refrigerating device, a chamber adapte to have one side thereof connected with a refrigerating system, a diaphragm dividing the aforesaid side, of saidchamber from the other side, means for directing a flow of fluid under pressure constantly to said diaphragm chamber to operate the diaphragm in one direction, and means forming a by-pass for the forced fluid flow to automatically release the pressure of said pressure fluid against said diaphragm to permit its return. V

2. In a refrigerating device, a diaphragm chamber having a refrigerant inlet and outlet on one side thereof,.a diaphragm separating the refrigerant side of said chamber fromthe other side thereof, a fluid chamber arranged below said diae phragm chamber communicating with the side of the diaphragm opposite to that of the re? frigerant, fluid pumping means supplying fluid under pressure to the latter chamber to operate the diaphragm, and a valve automatically and periodically releasing the fluid from said chamber to permit it to return to said pumping means.

3. In a refrigerating device, a chamber having an inlet valve and an outlet valve arranged at one-side thereof, a flexible diaphragm separating said chamber into two compartments, one communicating with said inlet and outlet valves, a chamber open to the compartment on the opposite side of the diaphragm, a pressure pump connected to the latter chamber and directing a flow of fluid under pressure thereto in a constant stream, a. relief chamber connected with the latter chamber, a balanced pressure valve closing said pressure chamber and adapted to periodically release the pressure into the relief chamber, and spring means for returning said valve to its closed position.

4. In a refrigerating device, a chamber having an inlet valve and an outlet valve arranged at one side thereof, ajflexible diaphragmseparating said chamber into two compartments, one communicating with said inlet and outlet valves, a chamber open to the compartment on the oppo site side of the diaphragm, a pressure pump .con-

nected to the latter chamber and directing a flow of fluid under pressure thereto in a constant stream, a port leading from the latter chamber, a spring loaded valve closing said port, achamber connected with said port havingan opening of greater area than said port, and a spring loaded valve closing the latter chamber and opening following the opening of the aforesaid valve.

5., A device as claimed in claim 4 having the smaller valvein the form of apiston slidably mounted in the larger valve and operating therewith to first close the smaller port and then the chamber directly connected therewith. V

6. In a refrigerating device, a chamber having an inlet valve and an outlet valve for the refrigerant arranged at one side thereof, a flexible diaphragm separating said chamber into two compartments, one communicating with said inlet and outlet valves, a chamber opento the compartment on the oppositeside of the diaphragm, a pressure pump connected to the latter chamber and directing a flow of fluid under pressure thereto in a constant stream, a port opening from the latter chamber, a chamber of greater diameter than the latter chamber and connected therewith by said port, a relief chamber communia, eating with the latter chamber and of considerably greater diameter, a piston valve slidably mounted to close the opening to the relief chains her, a coil compression spring housed in said valve for closing same, a piston valve mounted in the aforesaid valve and adapted to close said port, and a coil compression spring housed in the latter valve. 7 I e 7. In a refrigerating device, a casing having a flanged top formed with a central depression and a central recess below said depression, a screen covering said recess, a fluid pump having its discharge connected with said recess, a cap cover-,- ing the depression in said casing, inlet and outlet valves arranged in said cap controlling the flow of refrigerant to and from said depression, a displaceable diaphragm dividing the depression into upper and lower fluid-displacement come partments, a port, leading fromsaid recess into the interior ofsaid casing, a spring operated valve closing said port against the fluid pressure, a recess .in thecasing 'wallconnectedwith said port, a spring operated valve closing said recess and supporting the aforesaid valve, said latter 150V a casing having a displacement diaphragm subdividing the interior into respective chambers, inlet and outlet valves for the refrigerant associated with one of said chambers, a fluid-pumping means having its discharge connected'with the other of said chambers, and automatically operating pressure-controlled valve means for periodically releasing the pressure of the pumped fiuidon the diaphragm, and means for returning the released fluid to the pumping means.

HENRY HENDRIKS. WILLIAM A. DEAN. THOMAS W. CAMPBELL. 

